(The wind blows and the snow falls in the Antarctic region. Icebergs bob up and down within the rough ocean. In blizzard-like conditions,
a man with heavy-weather clothing is kneeling in the snow by a wall, digging with a small pickaxe. Another man joins him, wearing similar
clothes. He kneels and communicates with his companion, necessarily shouting because of the howling wind. The two men are Charles Winlett,
and Derek Moberley, workers on an Antarctic research station.)

MOBERLEY: Come on Charles, we've got enough samples, surely!WINLETT: This isn't ice - this is something else. Have a look.

(He reaches down and extracts a small round object, frozen with ice and snow, but unrecognizable to both men.)

MOBERLEY: What is it?WINLETT: Don't know! Let's get it back to camp.

(They both stand up ready to leave.)

2, INT: RESEARCH STATION - LABORATORY

(After an exterior shot of the research station, the round object is being examined on a table by the third member of the research
team, John Stevenson. He scrapes away the excess ice to reveal a solid, rough, dark green pod or egg. Moberley and Winlett enter.)

STEVENSON: The cutaneous creasing is unmistakable. When it's properly thawed out I can...confirm it with a cytology test.

(Winlett is prodding the pod with a scalpel.)

WINLETT: The skin looks as hard as iron.STEVENSON: Yes, it is a bit of a cannonball. How deep in the permafrost was it?WINLETT: About the er... 9th layer.MOBERLEY: And that means it's been there for ooh...20 thousand years? What do you make of it, John?STEVENSON: Nothing at all yet.MOBERLEY(joking): Oh, and I thought you were meant to be a botanist.STEVENSON: I've not seen anything remotely like it.WINLETT: It looks tropical to me, like a gourd.MOBERLEY: Oh rubbish Charles. If it's from the late Pleistocene period, it can't be tropical. It's a few million years since
this part of Antarctica was rainforest.WINLETT: Oh that's the accepted theory. Discoveries like this have destroyed accepted theories before now. Isn't that right,
John?

(Stevenson is far less casual about the situation than the others. Without even listening to Winlett, he hesitantly touches the pod
a few times with his finger. Winlett tries to get his attention but he seems distracted and confused.)

WINLETT: ...John?STEVENSON: ...hmm? Sorry.MOBERLEY: Is something wrong?STEVENSON: ...Don't you feel it?MOBERLEY: Feel what?STEVENSON: I don't know - there's something... odd...something...you don't feel it?MOBERLEY(laughing): It must be that rice pudding you had for lunch!

(Winlett laughs, but Stevenson doesn't. He steps closer to Moberley.)

STEVENSON: I'm not joking. ... ... It's alive. That's it. It's alive.MOBERLEY: Are you serious?!STEVENSON: Yes.WINLETT: How can you tell?STEVENSON: I don't know - but I'm certain that this is a living organism.

(Moberley breaks the intense atmosphere.)

MOBERLEY: ...Yes well I think we should have some coffee.WINLETT: Coffee and a game of three-handed crib. Come on!

(He takes Stevenson around the shoulders and leads him off. Stevenson doesn't relax, and he turns back to look at the pod.)

(A man in a suit is getting a file from a cabinet. He is Richard Dunbar of the World Ecology Bureau.)

DUNBAR: Sir Colin insists that I show you these photographs which have just been received from my expedition.

(As the camera follows him, it shows that it is the Doctor whom Dunbar is talking to. He is sitting on Dunbar's desk and he seems
more interested in his yo-yo than what Dunbar is saying.)

DUNBAR: Personally, I don't think you can help us.DOCTOR: Don't you? Well...

(Dunbar reluctantly hands him the file. Dunbar looks around uncomfortably.)

DOCTOR: Do sit down, Mr. Dunbar.

(Unable to sit in his own chair as the Doctor would be almost on top of him, he walks all the way around the far side of the desk
and sits in the chair usually provided for the visitors.)

DUNBAR: These pictures have baffled all the experts. The only reasonable explanation seems to be that the pod is from some
extinct species of plant.

(The Doctor spins around to face Dunbar, he sits in Dunbar's chair and there is a bang as he rests his boots on Dunbar's desk. He
doesn't look up from the file.)

DOCTOR: Have you considered an alternative explanation.DUNBAR: Name one.DOCTOR: Well...that it might have originated in outer space.DUNBAR(amused): My dear Doctor, if you've seen anything like that before, you must have a very powerful telescope.DOCTOR(unimpressed): Mr. Dunbar, how long is it since there was vegetation in Antarctica?DUNBAR: I thought you were the expert in these matters. Well as a matter of fact, that's one of the things our expedition is
trying to discover. It was found fairly deep in the permafrost; say...20-30 thousand years under the ice...DOCTOR: Ssh. It might still be ticking.DUNBAR: What?

(The Doctor suddenly seems interested and he stands up abruptly, walking around the desk.)

DOCTOR: A time-bomb, Mr. Dunbar, a time-bomb. Are you in contact with the expedition?DUNBAR: My superior, Sir Colin Thackeray has a daily video link. Ten minutes of satellite time.DOCTOR: Good. Tell them to keep a constant guard upon the pod, and not to touch it until I arrive.DUNBAR: You're leaving immediately?DOCTOR: Why not? I've got my toothbrush.

(He turns around and for some reason has a toothbrush in his hand. He starts to leave but ducks back in for a few more words.)

DOCTOR: Remember, no touch pod - could be dangerous.

(He shuts the door. Dunbar stares incredulously after him for a while, then turns to his desk and picks up a phone.)

DUNBAR: Sir Colin? Dunbar here. That chap you called in from UNIT - is he quite sane?!

4, INT: RESEARCH STATION - LABORATORY

(Stevenson measures the pod with a pair of pincers. He looks worried about the measurement and mutters to himself. He gets up and
goes to the door.)

STEVENSON: Charles?WINLETT(oov): Yes?STEVENSON: Here a minute.

(Winlett enters and they walk over to the table to look at the pod.)

WINLETT: What's up?STEVENSON: It's growing.WINLETT: Eh?STEVENSON: It's grown five centimetres since this morning.WINLETT: Are you sure?STEVENSON: Check it yourself if you don't believe me.WINLETT: But it doesn't seem possible.STEVENSON: I knew there was still life there - I said so didn't I?WINLETT: But it's just a pod, I mean...no root system. How can it grow without feeding?STEVENSON: Sunlight, Charles - ultra-violet radiation.WINLETT: But plants need nitrogen.STEVENSON: I believe this is fundamentally different. ... We may be cultivating something that is going to...shatter all our
ideas about plant growth.WINLETT: Yes, well er...don't get carried away John.

(He gets up and starts to leave.)

WINLETT: Remember what London said.STEVENSON: What do you mean?WINLETT: That we leave this thing alone.

(Stevenson looks annoyed and walks over to Winlett.)

STEVENSON: Until this Doctor character arrives, why should we? It's our pod.WINLETT: John, we're working for the World Ecology Bureau.STEVENSON: Oh he's probably some old crank that Thackeray's dug up out of retirement! He'd have no more idea about the pod than
we have.WINLETT: We'll soon find out, he's due in tomorrow.STEVENSON: And who needs him. It's our discovery. The less said about it the better.

5, INT: CHASE ESTATE - NURSERY

(There is a shot of a large mansion. Inside, a butler, Hargreaves, is showing a man into a nursery. The man is Dunbar. He carries
a suitcase. They approach the main part of the nursery, where a small man in a suit can be seen with his back to them. Hargreaves announces
Dunbar.)

HARGREAVES: Mr. Dunbar, of the World Ecology Bureau, sir.

(Hargreaves leaves. Dunbar waits for the man to turn around. Harrison Chase, owner of the mansion, is a small eccentric man wearing
a black suit and black gloves. Finally deciding to notice Dunbar, he walks towards him.)

CHASE: I don't think I've had the pleasure. And what is your bureau doing about bonsai?DUNBAR: Bonsai, Mr. Chase?CHASE: Mutilation and torture, Mr. Dunbar. The hideous, grotesque Japanese practice of miniaturizing shrubs and trees. What is
your bureau doing about that?DUNBAR: Well...I...CHASE: No answer. You are concerned about the fate of the blue whale, and the natterjack toad - and the loveliest, most defenceless
part of creation; the great kingdom of plant life receives no protection at all.DUNBAR: We try to conserve all the endangered species.CHASE: I'm delighted to hear that, Mr. Dunbar. Of course you know of my concern...my mission: to protect the plant life of Mother
Earth?DUNBAR: I do, Mr. Chase - which is why I've come to show you something. A totally new kind of plant.

(Dunbar opens his suitcase and retrieves some photographs.)

CHASE(angry): Hybrids! A crime against nature!DUNBAR: No, not a hybrid. It's a mysterious unidentified pod recently discovered by one of our expeditions.

(He hands the suddenly interested Chase the photographs.)

CHASE(excited): Where was this found?DUNBAR: There's a theory that it's floated through space from some other biosphere. The really important thing is, it may be
still viable and able to germinate.CHASE: Mr. Dunbar. I asked you where this pod was found.DUNBAR: In the Antarctic. Now in our violent and uncertain world, Mr. Chase, anything could happen. Such a valuable specimen
could easily disappear....for a price?CHASE: Where in the Antarctic? I should want to know the precise location.

(Dunbar gets an envelope from his pocket and hands it to Chase. Chase walks over and picks up a column-shaped object, an intercom
of some sort.)

SCORBY: You wanted to see me, Mr. Chase?CHASE: Yes, Scorby. I'm sending you on a little errand, and I want you to take Mr. Keeler with you.

6, INT: RESEARCH STATION - LABORATORY

(The pod sits in its place on the table. Winlett wakes up from a doze. He sips his coffee and puts the cup back down, resting his
arm near the pod. He looks at it for a while, then slowly drops back to sleep. Suddenly the pod starts to crackle and it opens outwards.
A long weed-like vine grows out from the pod and attaches itself to Winlett's arm! Winlett wakes up and is terrified. He struggles away
from the table, seemingly in great pain, staggering and falling onto the ground.)

WINLETT: Aaah....Derek...!

7, INT: RESEARCH STATION - LIVING QUARTERS

(Stevenson hears the scream and jumps off his bunk.)

STEVENSON: Was that Charles?MOBERLEY: What? What's happening?

(They both hurry out to find Winlett.)

8, INT: RESEARCH STATION - LABORATORY

(They find Winlett on the ground.)

STEVENSON: Charles?

(Stevenson rolls Winlett over onto his back, and alarmingly Winlett's face is now green and his skin is completely rough! His unconscious
eyes stare out into nothingness.)

9, INT: WORLD ECOLOGY BUREAU - OFFICE

(In the near future, Sir Colin Thackeray talks to Dunbar.)

THACKERAY: This Telex from Stevenson, what do you make of it?

(Dunbar picks up the piece of paper and reads it.)

DUNBAR: 'Pod carries infection, Winlett seriously ill, Medicaid needed urgently.' Could have been more informative, Sir Colin.THACKERAY: He probably doesn't know any more. I have ordered Medical Team to go to the base, but I understand the weather conditions
are bad. It's bound to take at least a day or two.DUNBAR: The people from UNIT should be arriving now, perhaps they can help.

10, EXT: RESEARCH STATION

(A helicopter begins to land near the base. A short time later, with heavy snow falling, Moberley comes out to greet the Doctor and
Sarah. Moberley and Sarah are dressed heavily, while the Doctor has not changed his attire at all. Everyone has to shout over the wind
and the noise of the helicopter.)

MOBERLEY: Hello! So you made it! Welcome to the loneliest spot on Earth. You must be the Doctor.DOCTOR: Yes.MOBERLEY: We were expecting someone much older.DOCTOR: Well I'm only 749, used to be even younger!MOBERLEY: Derek Moberley.SARAH: Sarah Jane Smith. The young Doctor's assistant.DOCTOR: How many of you live here?MOBERLEY: Anything up to a dozen, but of course we're down to three at the moment. Let's get inside...SARAH: Yes.DOCTOR: Where are the others?MOBERLEY: Out at the South Bend (?) not 60 miles away, measuring the ice caps, if they're getting this kind of weather they're
welcome to it! Come on.

(Much to Sarah's relief, they finally make it inside.)

11, INT: RESEARCH STATION - CORRIDOR

(Sarah removes a glove and puts her frozen finger in her mouth to warm it up.)

SARAH: How do you stand it?MOBERLEY: Oh, sometimes it gets quite warm. 10 degrees below freezing.SARAH: Crikey, I feel as though I've got frostbite already!MOBERLEY: I'll get you something hot to drink in a tick.

(He turns to the Doctor.)

MOBERLEY: Er, are you okay dressed like that, you don't seem to notice the cold.DOCTOR: I haven't come ten thousand miles to discuss the weather, Mr. Moberley; can I see the sick man?MOBERLEY: Yes of course, down this way.

12, INT: RESEARCH STATION - SICK BAY

(The now almost unrecognizable form of Winlett is lying on a bed. The Doctor and Stevenson stand nearby.)

STEVENSON: He seems to be conscious, but he hasn't spoken a word since last night.DOCTOR: What's his body temperature?STEVENSON: Well that's the amazing thing. I've been trying to keep him warm but it's dropping hourly.DOCTOR: And the pulse rate?STEVENSON: His body temperature is 46; his pulse rate is 18 a minute. I'm no medical expert, but on those figures he should be
dead, shouldn't he?DOCTOR: I wonder.

(The Doctor pulls back the sheet to reveal Winlett's body; no longer does he have human skin, and instead he is fully covered in
green plant-like skin.)

STEVENSON: Good grief! It wasn't like that an hour ago.DOCTOR: Then it's accelerating. How long before a medical team arrives?STEVENSON: Well it's difficult to say in these conditions. Hopefully tomorrow.DOCTOR: I don't think that's going to be soon enough, Mr. Stevenson.

13, INT: RESEARCH STATION - LIVING QUARTERS

(Moberley passes a cup of coffee to Sarah, who looks very cold.)

MOBERLEY: There, that ought to warm you up.SARAH: Thanks.

(She drinks some coffee.)

MOBERLEY: Better?SARAH: Mm. So you say you just found this pod lying there empty.MOBERLEY: Yes, and Charles in that state. Now does that make any kind of sense to you?

(An alarm goes off nearby.)

MOBERLEY: Would you excuse me? Radio.SARAH: Oh sure.

(He gets up.)

14, INT: RESEARCH STATION - SICK BAY

STEVENSON: Have you any idea what it could be, Doctor?DOCTOR: Yes. That's why I came here.STEVENSON: I thought you came here to see the pod.DOCTOR: Exactly - before anything happened. Unfortunately it already has! Where's the lab?STEVENSON: I'll show you.

MOBERLEY: Bad news, John. That was Mike Wilson at South Bend. The medical team's turned back.STEVENSON: What about Charles? Did you tell them how bad he is?MOBERLEY: They were in white out conditions and their Snow Cat's fallen intro a crevasse. But Mike is in touch with the Royal
Marine Survival Team - they might be able to help. They'll try again as soon as the weather lifts.STEVENSON: Well that'll be too late! He's dying! Isn't he Doctor?DOCTOR: No.STEVENSON: I thought you said in the sick bay...DOCTOR: It's more serious than death, Mr. Stevenson. He's changing form.STEVENSON: Changing form?DOCTOR: Yes. We need a blood test.MOBERLEY: I'm a zoologist - I could prepare a specimen slide if it'll help?DOCTOR: Yes it would help, thank you.MOBERLEY: Right.

(He leaves. The Doctor has only one word for Stevenson. He leans in closer and stares at him.)

DOCTOR: Pod.STEVENSON: It's over here.

(They move over and Stevenson picks up the tray with the opened pod on it. The Doctor examines it.)

DOCTOR(quietly, but furious): Why did it open? Why?STEVENSON: Well that...that could be my fault. It was frozen stiff when we took it out of the ice. I was certain there was still
life there. I put in under a lamp and it started to expand.DOCTOR: Mr. Stevenson, what you have done could result in the total destruction of all life on this planet.

(Stevenson stares back in disbelief.)

16, INT: RESEARCH STATION - SICK BAY

(Moberley takes the blood sample from Winlett. He puts it down and looks at the monster his friend has become. His condition is even
worse than before.)

MOBERLEY: Charles? We're trying our best Charles. Help's on its way.

(He gets up sadly and with one final look back, he leaves.)

17, EXT: ANTARCTICA

(A pickaxe is digging in the ice. It is the Doctor, covered in snow. Sarah and Stevenson watch nearby.)

SARAH: Doctor? Doctor, what are we looking for?DOCTOR: Are you sure this is the place, Stevenson?STEVENSON: Yes, and if you told us what you were doing, perhaps we could help.

(The Doctor doesn't even bother to look up. He keeps digging until he finds something in the ice.)

DOCTOR: Yes! Just as I thought!SARAH: Another pod!STEVENSON: How did you... ...Will there be any more?DOCTOR: No. They travel in pairs - like policeman.SARAH: What are we going to do with it - buy it a truncheon?DOCTOR: No. Take it into custody and keep it in the freezer.

18, INT: RESEARCH STATION - LABORATORY

(Night time, Stevenson puts the pod into a big freezer.)

STEVENSON: Well that ought to keep it cool.SARAH: Who sold you that, an Eskimo?STEVENSON: I know a freezer seems superfluous out here, but we do need it to keep snow sample in - until they're analysed.MOBERLEY(oov): Doctor?DOCTOR: Hmm?

(Moberley is looking in a microscope.)

MOBERLEY: Take a look at this blood sample.

(The Doctor goes over to look.)

DOCTOR: How's Winlett?MOBERLEY: Winlett. He's barely recognisable. It's as if he's turning into some sort of a hideous monster.DOCTOR: That's exactly what is happening, Moberley.MOBERLEY: Yes but there must be an answer.DOCTOR: You can just increase the magnification...ah...yes! Take a look at that.

(Moberley looks.)

MOBERLEY: These aren't blood platelets?DOCTOR(to Stevenson): Do you recognise them?

(Stevenson looks. He is shocked by what he sees.)

STEVENSON: Schizophytes.DOCTOR: Exactly.STEVENSON: I don't believe it. It's not possible.SARAH: Would someone mind explaining what these schizophytes are please?STEVENSON: The smallest known living organisms. Plant bacteria.SARAH: Plant bacteria, in someone's bloodstream?DOCTOR: Interesting, isn't it. A human being whose blood is turning into vegetable soup.SARAH: Listen...

(They hear the sound of engines.)

MOBERLEY: That's very low by the sound of it.STEVENSON: It's the medical aircraft. Quick Derek, get the landing strip (?) lights on.MOBERLEY: They won't see anything in this blizzard (?)

(They go back into the living quarters, their voices hard to hear over the engine noise.)

19, INT: RESEARCH STATION - LIVING QUARTERS

(Moberley and Stevenson are getting dressed to go outside.)

SARAH: Should we come out and help you?MOBERLEY: No, John and I know our way around out there - it's easy to get lost.SARAH: Okay.MOBERLEY: You ready?STEVENSON: Ready.MOBERLEY: Right.

(They leave.)

SARAH: Will they be able to help that man?DOCTOR: I don't know Sarah. He's halfway towards becoming a Krynoid.SARAH: Krynoid?DOCTOR: Yes. A progression of the pod.SARAH: So you recognised it.DOCTOR: Yes, I was fairly certain when I saw the photographs. Now I'm sure.SARAH: Well, what is a Krynoid? I mean, what does it do?DOCTOR: I suppose you could call it a galactic weed. Except it's deadlier than any weed you know.SARAH: In what way?DOCTOR: Well on most planets, the animals eat the vegetation, hmm?SARAH: Mmhmm.DOCTOR: On planets where the Krynoid gets established, the vegetation eats the animals.SARAH: But that's terrifying!DOCTOR: Yes.SARAH: Well how did it get through space?DOCTOR: An obvious question - I wish I knew the answer. Possibly their planet of origin is turbulent from time to time, that
any internal explosions could cause surface matter to go shooting into space...SARAH: So what do we do about Winlett?DOCTOR: I'm thinking Sarah, I'm thinking.

20, INT: RESEARCH STATION - CORRIDOR

(From outside, Moberley and Stevenson help two other men into the shelter, directing them down to the living quarters. All four men
are dressed heavily and covered in snow.)

21, INT: RESEARCH STATION - LIVING QUARTERS

(Sarah goes to help; the two new men are shown to chairs. The Doctor doesn't bother to help.)

(The two men are not the medical team though; it is Scorby and Keeler - on their 'errand'.)

STEVENSON: Get some brandy, Derek.MOBERLEY: Right.DOCTOR: Is this the medical team?STEVENSON: They were flying a private plane.MOBERLEY: They just got themselves lost. Brandy.

(He hands the two men cups. They thank him and drink it.)

KEELER: Sorry to be such a nuisance.SCORBY: Yeah, we were nearly out of fuel when we saw your lights.SARAH: You were very lucky; lights are few and far between out here.DOCTOR: I'd like to take another look at the patient.STEVENSON: What, now?DOCTOR: Now. Yes come on.STEVENSON: You just relax and __?SCORBY: Alright, thanks.

(The Doctor, Sarah, Moberley and Stevenson leave.)

KEELER: Do you think they swallowed it? If they start asking too many questions...SCORBY: Why worry, Keeler? What can they do?

22, INT: RESEARCH STATION - SICK BAY

(The four arrive in the sick bay to find Winlett totally transformed; a big green pile in only a vague human shape.)

SARAH: That's horrible. Horrible!DOCTOR: The process is almost complete.MOBERLEY: And we can do nothing except just watch it happen.DOCTOR: There is something you can do but it's drastic.STEVENSON: Well, what?DOCTOR: Amputate the arm.MOBERLEY: What good what that do? Can't you see the infection's all over his body?DOCTOR: Yes well the arm's the source of the infection - it might stop it spreading.MOBERLEY: You say might, what you mean is you don't know!DOCTOR: Well of course I don't know! But it would give you a breathing space while you try and find an antidote - that's a chance
worth taking isn't it?MOBERLEY: And who's going to perform this operation?DOCTOR: Oh you are, Moberley, you're the only one who can.MOBERLEY(horrified): But I'm not a surgeon...What about you, you're a doctor!DOCTOR: You must help yourselves.SARAH: He's not a doctor of medicine. Stevenson's a botanist, you're a zoologist. Ask yourself who is most qualified among us.MOBERLEY: But, I can't operate on Winlett - it's absurd!SARAH: Oh at least you could try. You studied physiology, you know how to handle a scalpel...MOBERLEY: To dissect dead specimens, yes, but Charles is a human being.SARAH: He won't be much longer if you don't operate! (to Stevenson) Look, have you got a medical kit?STEVENSON: We have a full medical kit in the lab.SARAH(to Moberley): Well? Well what about it? You're his last chance!STEVENSON: Derek, we'll help you in every way we can.

(Moberley is clearly horrified at what they are asking him to do. There is a long silence while he decides.)

(They leave. After they have all gone, the being that was once Winlett slowly sits up. It looks around the room - only one of its
eyes can be seen clearly.)

23, INT: RESEARCH STATION - LABORATORY

(Some solutions and medical instruments have been prepared. Moberley picks up the tray with the equipment on it.)

MOBERLEY: I'll take these down to the sick bay and start setting up.DOCTOR: You'll need more lights in there.STEVENSON: I can fix that.DOCTOR: Winlett's still got a chance.

24, INT: RESEARCH STATION - CORRIDOR

(Moberley walks down the corridor heading for the sick bay. He sees something and stops.)

MOBERLEY: Charles.

(The creature is in the shadows, leaning against the wall. It makes a sort of screeching sound. Moberley puts down the equipment
and walks towards his old friend. But the creature grabs him around the neck with tremendous power and throttles Moberley to the ground...)